Muscle-specific knockout of PKC-λ impairs glucose transport and induces metabolic and diabetic syndromes
J. Clin. Invest. 117:8 doi:10.1172/JCI31408 [Go to this article.]

Figure 3
Insulin signaling in muscle of homozygous and heterozygous KO mice.

(A) Effects of homozygous and heterozygous muscle-specific KO of PKC-λ on basal and in vivo insulin-stimulated activities of aPKC, PKB, and IRS-1–dependent PI3K in vastus lateralis muscles of homozygous KO versus WT and heterozygous KO versus heterozygous control mice. Experiments were conducted as described in Figure 1, A–D. Insets show representative autoradiograms of basal (–) and insulin-stimulated (+) IRS-1–dependent PI3K (IRS-1/PI3K) activity, i.e., ³²P-PI-3-PO₄ resolved by thin-layer chromatography. (B) Effects of PKC-λ KO on in vitro PIP₃-stimulated activity in aPKC immuno­precipitates obtained from basal (not stimulated by insulin) vastus lateralis muscles of heterozygous control and heterozygous KO mice. Note that absolute values of kinase assays varied considerably in different assays (e.g., aPKC values herein), most likely reflecting interassay differences of ATP-specific activity and/or enzyme recoveries or activities in immunoprecipitates; thus, absolute values can only be compared within the same assay. Values are mean ± SEM. n for each group is shown in parentheses. ^#P < 0.05; ^##P < 0.01; ^###P < 0.001 versus non–insulin-stimulated group of the same genotype (ANOVA). *P < 0.05; ***P < 0.001 (ANOVA).